1. Field of the Invention
The present invention relates in general to a remote-controllable laser projection apparatus. More particularly, the present invention provides a laser projection apparatus for projecting laser light onto an object, scanning the object, and forming horizontal lines, vertical lines, and oblique lines in order to use these lines for inking.
2. Description of Related Art
Laser projection apparatuses are widely used on construction sites, for example, to mark a horizontal line at a prescribed height on an indoor wall. Such a laser projection apparatus generates visible laser light and projects it via an optical system. A standard laser projection apparatus generally operates in distinct modes: 1) focus mode 2) rotation mode, and 3) scan mode.
During focus mode operation, the position of the focal point of the laser light is adjusted in response to the distance between the apparatus and a target object. The optical system for projecting is adjusted to sharpen the projection image of the laser light on the target object as much as possible.
In rotation mode, the laser light is rotated 360 degrees. The standard laser projection apparatus adjusts the rotation speed of the optical system, and forms a linear image that is suitable to be inked (marked) via. the residue image effect of the laser light on the target object. For example, when the target object is located far from the laser projection apparatus, the rotation speed of the optical system needs to be controlled below a certain level in order to secure a satisfactory level of luminance on the target object. On the other hand, when the target object is located near the laser projection apparatus, the standard laser projection apparatus can form a linear image of high luminance by increasing the rotation speed of the optical system. In the scan mode, the standard laser projection apparatus forms an image suitable for inking on the target object by, for example, adjusting the angular scan range at a constant rotation speed. If the target object is located far from the standard laser projection apparatus, the standard laser projection apparatus in the scan mode restricts the scan range in order to form an image suitable for inking on the target object.
During scan mode the laser light scans repeatedly within the range of a prescribed angle, and the like. Typically an operator of a standard laser projection apparatus manually selects or switches among operation modes and adjusts the operation parameters as the operator observes the image of the laser light on the target object.
However, since the target object is located at a predetermined distance from the laser projection apparatus, the operator needs to go toward the target object to observe the image of the laser light near the target object, and then return to the laser projection apparatus to adjust the laser projection apparatus by giving appropriate control signals to the laser projection apparatus. Since the operation mode needs to be switched or adjusted frequently, operation is very inefficient.
In order to control the laser projection apparatus, a remote controller that uses infrared light or radio waves can be used instead of the above-explained manual control method. However, such a remote controller is expensive, and thus undesirable.